https://community.appian.com/discussions/f/rules/4326/hi-all-how-do-i-convert-a-two-dimensional-array-of-cdt-array-and-flaHi All, How do I convert a two dimensional array of cdt array and flatten it into single dimension array of cdts? Basically need to do ....append(arrayOfCDTArray[1], arrayOfCDTArray[2], arrayOfCDTArray[2]....arrayOfCDTArray[n]) Thanks in advance. OriginalPostIDen-USTelligent Community 12https://community.appian.com/thread/64339?ContentTypeID=1Wed, 30 Jan 2019 14:38:33 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:92e86ae4-7591-4171-92cd-3cc2e082d4a0Mike Schmitt<p>This is a really old thread - in the time that&#39;s passed, we&#39;ve gotten the new <code>a!flatten()</code> function, which I believe would automatically handle this sort of use case.</p><div style="clear:both;"></div>https://community.appian.com/thread/64335?ContentTypeID=1Wed, 30 Jan 2019 11:50:32 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:4152fd77-3abf-4cc6-b7cf-0628c61dea48krishnac622Try reduce(fn!reduce,{},merge(arrayOfCDTArray))<br /> I think this should work for you.<div style="clear:both;"></div>https://community.appian.com/thread/15495?ContentTypeID=1Tue, 24 Feb 2015 06:27:36 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:63b35eb2-dcf5-4ad9-bc81-cc466cbad036praveenjThanks! That&#39;s what I thought but kept getting arrayoutofboundexception on reduce function call. Looks like I had an issue with the way array was constructed.<div style="clear:both;"></div>https://community.appian.com/thread/15492?ContentTypeID=1Tue, 24 Feb 2015 01:45:00 GMTd3a83456-d57b-489c-a84c-4e8267bb592a:327c2f36-cdde-4b5f-8410-2becd064ad64Conor CahillYou can try using reduce(fn!append,{},arrayOfCDTArray)<div style="clear:both;"></div>